stepwise regression
در نشریات گروه باغبانی-
با توجه به اهمیت اقتصادی عملکرد میوه و لزوم انتخاب گیاهان با بهره وری بالا در برنامه های به نژادی، پژوهش حاضر به منظور تعیین ویژگی های مورفولوژیک تاثیرگذار در عملکرد میوه و ارزیابی اثرات مستقیم و غیرمستقیم آن ها در 30 توده ی فلفل ایرانی در قالب طرح کاملا تصادفی با پنج تکرار به صورت گلدانی در محل گلخانه تحقیقاتی دانشگاه ارومیه طی سال 1396-1395 اجرا گردید. نتایج حاصل از همبستگی های فنوتیپی نشان داد که عملکرد میوه دارای همبستگی مثبت و معنی دار با صفات قطر میوه، دور میوه، وزن گوشت و وزن تک میوه بود، اما صفات تعداد میوه و طول میوه همبستگی فنوتیپی منفی و معنی داری با عملکرد میوه داشتند. در بررسی همبستگی ژنتیکی، رابطه مثبت، قوی و معنی داری بین عملکرد با وزن گوشت میوه (907/0)، دور میوه (891/0)، قطر میوه (697/0)، وزن تک میوه (646/0) و دور بوته (381/0) مشاهده گردید. بر اساس نتایج رگرسیون گام به گام برای عملکرد میوه هفت صفت وزن گوشت، دور بوته، قطر میوه، تعداد میوه، ارتفاع بوته، وزن کل بذر و تعداد شاخه به عنوان موثرترین صفات بر عملکرد میوه وارد مدل شدند که در مجموع 6/84 درصد از تغییرات کل عملکرد میوه را توجیه نمودند. بر اساس نتایج تجزیه مسیر صفات قطر میوه (709/0) و وزن گوشت (289/0) به ترتیب بیشترین اثر مثبت و مستقیم را بر عملکرد میوه نشان دادند. قطر میوه دارای همبستگی ژنتیکی مثبت، قوی و معنی داری (697/0) با عملکرد میوه بود، همچنین اثر مستقیم مثبت (709/0) بر عملکرد میوه نشان داد که به طور تقریبی می توان این دو ضریب را با هم برابر درنظر گرفت. لذا انتخاب مستقیم از طریق صفت قطر میوه می تواند در بهبود عملکرد میوه در توده های فلفل مفید باشد.کلید واژگان: تجزیه ضرایب مسیر، رگرسیون گام به گام، عملکرد میوه، فلفلIntroductionPepper is a rich source of essential vitamins and minerals. Like tomatoes, pepper plays an important role in preventing heart diseases due to its high amount of antioxidants. Fruit yield is a complex trait that is not only controlled by several genes, but also greatly influenced by the environment. On the other hand, fruit yield is affected by a large number of other traits and their interaction. Therefore, it is very important for plant breeders to know the relationships between these traits and their interaction effects. The path coefficient analysis is a method that clarifies the relationships between traits and their direct and indirect effects on fruit yield. In this method, the correlation coefficient between two attributes is divided into components that measure direct and indirect effects. Considering the limited studies regarding the evaluation of relationships between fruit yield and other traits affecting fruit yield in pepper, this research was conducted with the aim of identifying these important relationships and evaluating their direct and indirect effects in Iranian pepper populations.
Materials and MethodsIn order to carry out this research, the seeds of 30 Iranian pepper accessions were collected directly from the farmers. The experiment was conducted in the form of pot cultivation in the research greenhouse of the Faculty of Agriculture of Urmia University in a completely randomized design with five replications during 2015-2016. After the flowering stage, the desired traits were estimated. Variance analysis was estimated, after examining the basic hypotheses of variance analysis by SAS9.4, as well as the genotypic and phenotypic correlation between traits based on the restricted maximum likelihood (REML) procedure in the SAS9.4 software. Step-by-step regression analysis was used to determine the traits with the most variation justified the fruit yield. The Durbin-Watson test was performed to investigate the independence of experimental errors. Analysis of path coefficients was performed based on the results of stepwise regression and genotypic correlation of traits in the R V.4.0.5.
Results and DiscussionIn order to understand the relationships between traits and use them in breeding programs, the phenotypic correlation was estimated. In this study based on the results of phenotypic correlation, leaf width and leaf length (0.651), single fruit weight and fruit circumference (0.784), fruit circumference and fruit diameter (0.625) and pulp weight and fruit diameter (0.610), showed positive and significant correlation. The purpose of estimating genotypic correlation coefficient is to determine relationships in conditions which in environmental factors are not involved. In the investigation of genotypic correlation, a positive, strong and significant relationship between fruit yield and pulp weight (0.907), fruit circumference (0.891), fruit diameter (0.697), single fruit weight (0.646) and around the plant (0.381) were observed. Given that most of these traits are factors contributing to fruit yield, the presence of such positive and significant genotypic correlation coefficients is reasonable. It can be inferred that pepper accessions with higher fruit characteristics, encompassing factors such as plant density and branching, are likely to exhibit higher fruit yields as well. It's important to note that correlation coefficients are mathematical tools used to measure the linear relationship between two variables. Their significance lies in their mathematical interpretation, and as such, they alone do not provide sufficient proof of a cause-and-effect relationship. Utilizing the results of stepwise regression, less impactful traits or those with minimal effects were eliminated from the model. As a result, seven key traits were identified as the most influential factors affecting fruit yield: pulp weight, plant density, fruit diameter, fruit count, plant height, total seed weight, and branch count.The first characteristic was pulp weight, which was included in the model and explained 78.8% of the fruit yield changes between genotypes. The second characteristic (around the plant) along with pulp weight explained 80.9% of the fruit yield variations. Fruit diameter, together with the previous two characteristics, explained 81.5% of fruit yield variations. In total, the traits included in the model for fruit yield justified 84.6% of the total changes in fruit yield in 30 pepper accessions. In order to better understanding and more accurately interpret of the results, as well as to know the direct and indirect effects and the effect of the traits that were entered into the model through stepwise regression, the path coefficient analysis method was used in this research. Fruit diameter (0.709) and pulp weight (0.289) respectively showed the most positive and direct effect on fruit yield. Fruit pulp weight through fruit diameter had the most positive indirect effect (0.595) on fruit yield. Around the plant showed an indirect positive effect on fruit yield through pulp weight (0.157), fruit diameter (0.392) and number of branches (0.080).
ConclusionIn the present study, the trait of fruit diameter had a positive, strong and significant genotypic correlation (0.697) with fruit yield, and it also showed a positive direct effect (0.709) on fruit yield, these two coefficients can be considered equal, Approximately. Therefore, direct selection based on fruit diameter proves to be a valuable strategy for enhancing fruit yield. The magnitude of residual effects serves as an indicator of the model's accuracy in path analysis. When this value is substantial, it may be advisable to incorporate additional causal variables into the model. In the current study, the residual effects value (0.213) affirms the model's optimal accuracy.This research highlights the effectiveness of employing stepwise multivariate regression and path coefficient analysis to gain a deeper understanding of the fundamental relationships between traits. It underscores that relying solely on correlation relationships is insufficient for comprehensively justifying the associations between these traits.Keywords: Fruit yield, Path coefficient analysis, Pepper, Stepwise regression -
یکی از مشکلات اساسی تولید گیاهان زراعی در کشور ما اختلاف بین عملکرد واقعی کشاورزان و عملکرد قابل حصول یا همان خلاء عملکرد می باشد. به منظور بررسی عوامل مدیریتی موثر بر کاهش عملکرد دانه گندم در منطقه ماهدشت کرج، آزمایشی به صورت میدانی در سال زراعی 97-1396 در مزارع منطقه ماهدشت صورت گرفت. در این تحقیق با استفاده از رگرسیون گام به گام سهم کلیه عوامل مدیریتی که ممکن است درکاهش عملکرد نقش داشته باشد تعیین گردید. نتایج همبستگی بین عوامل مختلف نشان داد عملکرد دانه با مقادیر تعداد دفعات آبیاری، مصرف نیتروژن در مرحله دوم، کل نیتروژن مصرفی در طول دوره رشد و مصرف ریز مغزی همبستگی مثبت و معنی داری در سطح احتمال 1 درصد و با سطح زیر کشت همبستگی مثبت و معنی داری در سطح احتمال 5 درصد دارد. با توجه به مقادیر عملکرد گندم ثبت شده، میانگین عملکرد واقعی دانه گندم 4775 کیلوگرم در هکتار به دست آمد و عوامل موثر بر کاهش عملکرد در این منطقه شامل تعداد دفعات آبیاری (42 درصد)، سطح زیر کشت (9 درصد)، محصول قبلی کشت شده (6 درصد) و کل نیتروژن مصرفی (5 درصد) تعیین گردید. دیگر عوامل مدیریتی تاثیر ناچیزی در کاهش عملکرد از خود نشان دادند. عملکرد دانه پتانسیل در منطقه ماهدشت کرج طبق مدل رگرسیونی تا 7630 کیلوگرم بر هکتار قابل ارتقاء می باشد که خلاء عملکرد در این منطقه حدود 2860 کیلوگرم بر هکتار به دست می آید.
کلید واژگان: رگرسیون گام به گام، خلا عملکرد دانه، گندمOne of the main problems of crop production in our country is the difference between the actual grain yield of farmers and the achievable grain yield or the yield gap. In order to investigate the management factors affecting the reduction of wheat yield in Mahdasht of Karaj, a field experiment was conducted in the crop year 2017-18 in the farms of Mahdasht which was previously selected by the researcher. In this study, using stepwise regression, the contribution of all management factors that may play a role in reducing yield has been investigated. The results of correlation between different factors showed a positive and significant correlation between grain yield with the number of irrigations, nitrogen application in the second stage, total nitrogen consumption during the growing period and micronutrient consumption at a probability level of 1%, and there was a positive and significant correlation with the area under cultivation at the 5% probability level. According to the recorded wheat grain yield values, the average actual wheat grain yield was 4775 kg.ha-1 and factors affecting yield reduction in this area including the number of irrigations (42%), area under cultivation (9%), previously cultivated crop (6%) and total nitrogen consumption (5%) were determined. Other management factors had little effect on grain yield reduction. Potential grain yield in Mahdasht of Karaj according to the regression model can be raised to 7630 kg.ha-1, and the grain yield gap in this area is 2860 kg.ha-1.
Keywords: stepwise regression, Grain yield gap, Wheat -
سیر ایران از کیفیت عطر و طعم خوبی برخوردار است، ولی تا به امروز به جز رقم مازند که مناسب مازندران است، رقم بومی دیگری از سیر اصلاح و معرفی نشده است. به منظور شناسایی پربازده ترین توده های محلی برای اصلاح و معرفی رقم مناسب شرایط آب و هوایی همدان، در سال زراعی 95-1394 آزمایشی بر روی 18 توده محلی مختلف در قالب طرح بلوک های کامل تصادفی با چهار تکرار در مرکز تحقیقات کشاورزی همدان اجرا شد. نه توده از مناطق کشت سیر استان همدان و نه توده از سایر استان های سیرکار کشور انتخاب گردیدند. توده های محلی از نظر 33 صفت مهم زراعی- مورفولوژیکی از جمله عملکرد سوخ؛ و میزان اسیدپیروویک کل (مجموع اسید پیروویک حاصل از فعالیت های آنزیمی و غیرآنزیمی)، میزان اسید پیروویک غیرآنزیمی، میزان اسید پیروویک آنزیمی و میزان آلیسین مورد بررسی قرار گرفتند. نتایج این بررسی نشان داد که صفات مورد بررسی توده های محلی کشور از تنوع بالایی برخوردارند که لازمه برنامه های اصلاحی است و همچنین معرفی توده ها به مناطق دیگر می تواند با نتایج مطلوب همراه باشد. چنانکه از نه توده محلی غیر بومی همدان سه توده محلی ارومیه، اراک و بردسیر کرمان در شرایط آب و هوایی همدان تولید قابل قبول داشتند. توده های محلی ارومیه، سولان و حیدره بر اساس عملکرد سوخ، اسید پیروویک آنزیمی و رابطه مولی دو به یک آن با آلیسین بیشترین ماده عطر و طعم دهنده آلیسین را در هکتار تولید کردند. صفات وزن سوخ به طور مستقیم و قطر یقه به طور غیرمستقیم از طریق وزن سوخ، با عملکرد سوخ و صفات شاخص سطح برگ، شاخص برداشت، وزن خشک برگ بوته و قطر سوخ با میزان آلیسین تولیدی ارتباط معنی دار بالایی نشان دادند. بر اساس تجزیه خوشه ای توده ها به دو گروه اصلی مناسب و نامناسب کشت در همدان تقسیم شده که گروه مناسب کشت در همدان خود به چهار زیرگروه سه تایی تقسیم شد. خوشه بندی امکان کاهش هزینه های حفظ منابع ژنتیکی سیر را با کم کردن میزان مواد نگهداری شده با حداقل افت تنوع صفات، فراهم می سازد.
کلید واژگان: اسید پیروویک، تجزیه خوشه ای، تنوع ژنتیکی، رگرسیون گام به گام، سیرIntroductionGarlic is native to central Asia, with a three thousand years history of human consumption and use. Global consumption has increased fourfold during the 24-years period from 1989 to 2013. Area under garlic cultivation, average yield/ha and total production of the world were 1,468,811 ha, 18,092 kg/ha and 26,573,001 tons, respectively in 2016; and China produces about 80% of world garlic production. The maximum global record has been registered at 2012 with an average bulb yield of 45,270 tons per hectare belongs to Uzbekistan. The area under cultivation of this plant in Iran is about 9000 hectares with an average yield of 10 tons per hectare. Garlic has been used both as a food flavoring and as a traditional medicine, and these characteristics are affected by sulfur compounds. Alliin (C6H11NO3S) with 177.22 molecule weight is a sulfoxide that is a natural constituent of fresh garlic. It is a derivative of the amino acid cysteine. When fresh garlic is chopped or crushed, the alliinase enzyme, which contains pyridoxal phosphate (PLP), cleaves alliin, generating allysulfenic acid, pyruvate (C3H4O3), and ammonium (NH3). At room temperature two moles of allysulfenic acid as an unstable and highly reactive compound that through a dehydration reaction form one mole of allicin (C6H10OS2) with 162.26 molecule weight, which is responsible for the aroma of fresh garlic. In general, alliinase needs few minutes time to effect on every two molecules of alliin to form one molecule of allicin, two molecules of pyruvate and two molecules of ammonium. The generated allicin is unstable and quickly breaks down, for example during sixteen hours at 23°C it converts to a series of other sulfur-containing compounds such as diallyl disulfide. Allicin is part of a common defense mechanism in garlic plants against pest attacks. It is produced and activated after causing physical injuries. Iranian garlic has a good flavor, while with the exception of Mazand cultivar so far there is no other introduced bred cultivar. In this effort, diversity of agromorphological traits, bulb yield and allicin content of some Iranian landraces were studied to breed promising cultivar/s by single-bulb selection method for Hamedan climatic condition.
Materials and MethodsThe experiment was carried out on the basis of a randomized complete block design (RCBD) with four replications in 2015-16 agronomy season at the Agricultural Research, Education and Natural Resources Center of Hamedan Province Located about 6 km north of Hamedan at the altitude of 1740 meters above sea level, longitude 48°, 52̍ E, latitude 34°, 52̍ N. The soil texture of the test site was loam with 24.4, 40.6 and 35 percent of clay, silt and sand, respectively. The soil tillage operation included plowing with the moldboard plow, disc and leveler. The furrow and stack were created with a width of 50 cm. Nine landraces from Hamedan province (Maryanaj, Bahar, Sheverin, Soolan, Toyserkan, Heidareh, Toeen, Hossein Abad and Ali Abad, and other nine ones from Gorgan (Golestan), Oromyeh (West Azarbaijan), Arak (Markazi), Bardsir (Kerman), Amol (Mazandaran), Ramhormoz (Khuzestan), Isfahan (Isfahan), Tarom (Zanjan) and Zabol (Sistan) cultivated on plots having 2 ridges with 4 meters long. Two rows were planted on the ridge with 25 and 10 cm spacing between rows and plants on the row, respectively (40 plant m-2). Bulb planting was carried out on November 17th, and first irrigation was rain-fed on 18th and 19th of November, with 19 and 9.9 mm rain, respectively, and during the fall and winter seasons, all water requirements were met through precipitation. Different landraces germinated from March 12th to March 16th. Pressure irrigation system was installed by re-growing in spring and plants were irrigated every seven to 10 days, depend on air temperature severity, until June 5th. Harvesting of different landraces was carried out by hands from June 26th to July 6th. Evaluated traits for each plot included weight of 30 seed clove, date of germination and maturity, number of plant per plot, chlorophyll a and b and carotenoids content of leaf, chlorophyll index by SPAD, relative water content of leaf, bulb yield, and weight of 30 produced clove, total pyruvic acid, and non-enzymatic pyruvic acid. The evaluated traits for five normal random plants (healthy plants on both sides, and on the opposite side of cultivation lines adjacent to the healthy plant) of each plot were including height, crown diameter, number of leaf, number of fallen leaf, length and width and leaf area, dry weight of plant leaf, dry weight of plant root (to a radius of five centimeters around the bulb) height and width and length of bulb, dry matter of bulb, number of skin layers, number and weight of clove, dry matter percentage. Assessment were also considered based on traits such as, moisture percentage of bulb, leaf area index, sum of chlorophyll a and b, loss weight of cuddle, harvest index, sphericity coefficient of bulb, total number of plant leaf, days number of germination to maturity, enzymatic pyruvic acid and allicin. Traits measurements were done based on "Descriptors for Allium". To measure pyruvic acid, 25 g of cloves with 25 ml of water were completely homogeneous in a mixer and passed through a filter paper after ten minutes. Ten ml of filtrated extract was increased into 100 ml volume with water and a half-milliliter of it was taken and added to 1.5 ml of 5% trichloroacetic acid solution, and after one hour, 18 ml of water was added to sample. Then one ml of resulting solution and each standard solution were transferred to separate test tubes. One ml of water and dinitrophenyl hydrazine 0.0125%, were added to each sample, and were heated in bain-marie bath at 37°C for ten minutes. At the end, by adding five ml of 0.6% normal caustic soda to the test tubes, the concentration of samples were determined in the presence of standard solutions (0.01, 0.225, 0.05, 0.1 and 0.2 μmol / ml sodium pyruvate) at 420 nm wavelength using spectrophotometer Pharmacia-Biotech model Novaspec II. To assess non-enzymatic pyruvate activity, alinase enzyme must become inactivated, so 40 to 60 grams of garlic clove is initially heated in microwave at 900 watts for three seconds for every gram of sample (120 to 180 seconds). To find relationship between variables, the correlation coefficients between them were calculated. The study of the relationship between traits with bulb yield and alicin yield was done by stepwise regression method. Causal relationships and direct and indirect effects of traits on bulb and allicin were determined by path analysis method. Analysis of variance, mean comparison of traits by LSD method at 1% probability level, correlation determination, stepwise regression analysis and cluster analysis were done by Minitab software version 17.3.1, while Microsoft Word and Excel 2003 softwares were used to draw the graphs and path analysis, respectively.
Results and DiscussionThe results shown that Iranian garlic landraces have noticeable diversity of agro-morphological traits, such as weight of 30 seed clove from 21 (Ramhormoz landrace) to 177 g (Hossein Abad landrace), bulb yield from 2059 (Ramhormaoz landrace) to 12090 kg ha-1 (Soolan landrace), Allicin yield from 4.9 (Ramhormoz landrace) to 53 kg ha-1 (Ali Abad landrace), bulb weight from 12.8 (Ramhormoz landrace) to 48 g (Bardsir landrace) and bulb diameter from 28 (Isfahan landrace) to 35 mm (Hossein Abad landrace), which are necessary for breeding programs. It is also confirmed that the adapted landraces from one region may have acceptable production in other regions. According to the present results, landraces from Oromyeh (10866 kg/ha), Arak (9941 kg/ha) and Bardsir (11444kg/ha) produced high yield in Hamedan climatic condition, so that the maximum allicin content were produced by landraces from Ali Abad (53 kg/ha), Maryanaj (51 kg/ha) and Oromyeh (51 kg/ha). Allicin content is calculated based on the bulb yield, and enzymatic pyruvic acid content and its molar relationship with allicin. In the recommended equilibrium of chemical reaction, the alliin coefficient on the one side is two and the coefficients of allicin and pyruvic acid on the other side are two and one, respectively. Bulb weight directly and crown diameter indirectly had highly correlation with bulb yield; and leaf area index, harvest index, bulb diameter and dry weight of plant leaf showed a high correlation with allicin content. The cluster analysis used standardized traits to divide landraces into two main groups as suitable and unsuitable sets to plant under Hamadan climatic conditions.
ConclusionAccording to the results of the present study, it is recommended that Oromyeh, Soolan and Heidareh landraces can be used as valuable populations for breeding and introducing the suitable cultivars for Hamedan climatic condition through single-bulb selection method. Characteristics with easy and low cost assessment, such as crown diameter, leaf area index, bulb diameter under field condition; and after harvest measurements, such as bulb weight, harvest index, dry weight of plant leaf traits can also be considered as suitable selection indicators in breeding programs. Thirdly, the current study indicated that the cost of preserving garlic germplasm resources can be decreased by reducing the amount of stored materials, without the significant decline in genetic diversity.
Keywords: Cluster analysis, Garlic, Genetic diversity, Pyruvic acid, Stepwise regression -
برآورد ضرایب همبستگی بین صفات مختلف، نه تنها می تواند سبب تسریع برنامه های اصلاحی گردو شود، بلکه امکان بهبود سایر صفات را در کنار اصلاح برای صفات موردنظر فراهم می کند. بدین منظور، داده های حاصل از دو سال ارزیابی مورفولوژیک 325 ژنوتیپ های انتخابی از استان های فارس، مازندران و ایلام جهت مطالعه همبستگی بین صفات مورفولوژیک مورد استفاده قرار گرفت. همچنین به منظور مطالعه همبستگی بین صفات بیوشیمیایی و مورفولوژیک، خصوصیات بیوشیمیایی تعداد 52 ژنوتیپ برتر از 325 ژنوتیپ اولیه مورد ارزیابی قرار گرفت. بررسی نتایج این پژوهش نشان داد که رابطه ی خطی و معنی داری بین صفات فنولوژیک به ویژه تاریخ برگدهی با تاریخ برداشت وجود داشت که از آن می توان جهت تعیین تاریخ برداشت بر مبنای تاریخ برگدهی استفاده کرد. عملکرد با تاریخ برگدهی (**58/0)، وزن میوه (**64/0) و مغز (*46/0)، اندازه میوه (**56/0) و عادت باردهی جانبی (**53/0) همبستگی مثبت و با رنگ مغز (*38/0-) همبستگی منفی داشت که با توجه به نتایج حاصل رگرسیون گام به گام، عادت باردهی جانبی، وزن میوه و شاخص اندازه میوه از اجزای اصلی تعیین کننده عملکرد گردو بودند. بررسی همبستگی بین صفات بیوشیمیایی با ارتفاع از سطح دریا و صفات مورفولوژیک نشان داد که درصد روغن و پروتئین موجود در مغز گردو تحت تاثیر خصوصیات فیزیکی میوه (اندازه و وزن میوه و مغز) نمی باشد. در مقابل، با افزایش ارتفاع از سطح دریا، درصد روغن و پروتئین موجود در مغز افزایش یافت. همبستگی منفی و معنی داری بین میزان اسیدهای چرب غیراشباع با یک باند مضاعف (MUFA) و اسیدهای چرب غیراشباع با چند باند مضاعف (PUFA) و همچنین بین نسبت PUFA:SFA با ضخامت پوست سخت مشاهده شد.کلید واژگان: اندازه میوه، تنوع ژنتیکی، درصد روغن، رگرسیون گام به گام، ضریب همبستگی، عملکردEstimation of correlation coefficients can accelerate walnut breeding programs and provide the ability to improve other traits along with targeted breeding traits. For this purpose, data obtained from two-year morphological evaluation of 325 screened genotypes from Fars, Mazandaran and Ilam provinces were used to study the correlation between morphological traits. In addition, in order to study the correlation between biochemical and morphological traits, biochemical characteristics of 52 superior genotypes out of 325 screened genotypes were evaluated for one year. Based on the results, a linear and strong relation was observed between phenological traits especially budbreak and harvest date. Yield had a positive and strong correlation with budbreak date (0.58**), nut weight (0.64**), kernel weight (0.46*), nut size (0.56**) and lateral bearing (0.53**) and a negative correlation with kernel color (-0.38*). Based on the result of stepwise regression analysis, nut weight, lateral bearing and nut size index were the main components of walnut yield. Correlation study between biochemical traits with altitude and morphological traits showed that oil and protein percentage of walnut kernel was not affected by the physical characteristics of the nut (nut and kernel size and weight). In Contrast, the oil and protein content increased with increasing altitude. A strong and negative correlation was observed between MUFA and PUFA. Also, PUFA: SFA ratio negatively correlated with shell thickness.Keywords: Nut size, Genetic diversity, oil percentage, Stepwise regression, correlation coefficient, yield
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International Journal of Horticultural Science and Technology, Volume:6 Issue: 1, Winter-Spring 2019, PP 137 -150By applying multivariate statistical analysis, this research aimed to estimate the heritability and find relationships between the vegetative and reproductive characteristics of Prunus scoparia and Prunus elaeagnifolia. Twenty genotypes of each species were selected randomly from cultivated populations and twenty-two traits including the tree, leaf, flower, nut and kernel attributes were measured. Results showed that there were high levels of genotypic and phenotypic variations among the genotypes of both species. Many of the measurements pertaining to the leaf, flower, nut and kernel, showed very high heritability (H2 >90%) in both species, whilst some traits such as shoot diameter in P. scoparia and kernel moisture in both species had very lower heritability (H2 <50%). Generally, the heritability of measured traits in P. elaeagnifolia were higher than those of P. scoparia, especially foreconomically important traits including yield (H2 = 94 and H2 = 54.61, respectively in P. elaeagnifolia and P. scoparia), nut weight (H2 = 97.83 and H2 = 85.39.61, respectively in P. elaeagnifolia and P. scoparia) and oil percentage (H2 = 75.55 and H2 = 61.43, respectively in P. elaeagnifolia and P. scoparia). Stepwise regression analysis revealed that the most influential factors on yield of P. scoparia, were the fruit set, flower diameter and leaf length, whilst for the P. elaeagnifolia, the yield was mostly determined by fruit set and leaf area. The high genetic diversity and heritability of the studied traits, indicates high genetic potential of this germplasm to be utilized in future breeding programs.Keywords: Wild almond, Breeding, Stepwise regression, cluster analysis, Bi-plot
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مجله تحقیقات گیاهان دارویی و معطر ایران، سال سی و پنجم شماره 2 (پیاپی 94، خرداد و تیر 1398)، صص 222 -239شناسه دیجیتال (DOR):98.1000/1735-0905.1398.35.222.94.2.1575.32 زنیان (Trachyspermum copticum L.)، یکی از گیاهان معروف خانواده چتریان است که از نظر تولیدات دارویی و اقتصادی دارای اهمیت می باشد. به منظور تعیین مهمترین صفات موثر بر عملکرد دانه، آزمایشی به صورت کرت های خردشده در دو شرایط آبیاری معمولی و تنش خشکی به عنوان عامل اصلی و 36 اکوتیپ زنیان متعلق به 9 استان مختلف کشور به عنوان عامل فرعی در قالب طرح بلوک کامل تصادفی با دو تکرار طی دو سال زراعی در کرمان انجام شد. نتایج تجزیه رگرسیون چندگانه خطی به روش گام به گام نشان داد که در شرایط تنش خشکی صفات تعداد چتر در بوته، تعداد دانه در چتر و عملکرد اسانس و در شرایط آبیاری معمولی صفات عملکرد بیولوژیک، وزن هزاردانه و تعداد دانه در چتر بیشترین تاثیر را بر عملکرد دانه داشتند که به ترتیب 87% و 99% از تغییرات به وسیله این صفات در دو شرایط تبیین شد. براساس نتایج تجزیه علیت، صفات تعداد چتر در بوته در شرایط تنش و عملکرد بیولوژیک در شرایط نرمال بیشترین اثر مستقیم را بر عملکرد دانه داشتند و به عنوان مهمترین اجزای عملکرد دانه شناخته شدند. این صفات می توانند به عنوان معیارهایی مناسب برای تسهیل فرآیند انتخاب غیرمستقیم و بررسی توانمندی عملکرد دانه در برنامه های به نژادی زنیان مدنظر قرار گیرند .کلید واژگان: تجزیه علیت، خشکی، رگرسیون گام به گام، زنیان (Trachyspermum copticum L، )Ajowan (Trachyspermum copticum L.), belonging to the Apiaceae family, is remarked as an important pharmaceutical and economical product. In order to determine the most important traits affecting grain yield, a split plot experiment was conducted in two conditions of irrigation (normal and drought stress) as the main factor and 36 ecotypes of ajowan, belonging to nine different provinces of Iran, as a sub plot based on a randomized complete block design with two replications in 2015 and 2016 crop year in Kerman. The results of linear multiple regression analysis with stepwise method showed that in drought stress condition, number of umbrellas per plant, number of seeds per umbrella and essential oil yield, and in normal irrigation conditions, biological yield, 1000-seed weight and seed number per umbrella had the highest effect on grain yield, explaining 87% and 99% of the changes, respectively. Based on the results of path analysis, traits including number of umbels per plant under stress conditions and biological yield under normal conditions had the most direct effect on the grain yield and were recognized as the most important components of the grain yield. Therefore, these traits can be considered as main appropriate criteria for facilitating the indirect selection process and evaluating the seed yield potential in ajowan breeding programs.Keywords: path analysis, drought, stepwise regression, C. copticum
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به منظور بررسی تنوع ژنتیکی 65 لاین فلفل، که از مناطق مختلف کشور و همچنین از کشور چین و مرکز تحقیقات بین المللی سبزیجات (AVRDC) جمع آوری شده بودند؛ آزمایشی به صورت طرح بلوک های کامل تصادفی با سه تکرار برای ارزیابی 13 صفت مرفولوژیک اجرا شد. نتایج حاصل از تجزیه واریانس حاکی از تفاوت معنی دار بین ژنوتیپ ها در سطح احتمال یک درصد از لحاظ تمامی صفات بود. بر اساس مقایسه میانگین صفات مختلف که به روش توکی در سطح احتمال 5 درصد انجام شد، ژنوتیپ های 3095 و 0013 و 26-6 از لحاظ عملکرد و خصوصیات مرتبط با بازارپسندی محصول وضعیت بهتری داشتند. برای تعیین فاصله ژنتیکی و گروه بندی ژنوتیپ ها، تجزیه به عامل ها و تجزیه خوشه ایانجام شد. جهت درک بهتر از روابط داخلی صفات و تعیین گروهی متغیرهای با بیشترین همبستگی، از تجزیه به عامل ها با استفاده از تجزیه به مولفه های اصلی و چرخش عامل ها به روش وریماکس استفاده شد. در این تجزیه چهار عامل مستقل از هم، مجموعا 07/74 درصد از تغییرات را توجیه نمودند. تجزیه خوشه ایبه روش وارد، لاین های ارزیابی شده را در شش گروه متفاوت قرار داد؛ به طوری که این نتایج تا حد زیادی با مناطق جغرافیایی پراکنش لاین ها و همچنین با صفاتی همچون عملکرد و خصوصیات مورفولوژیک مرتبط با بازارپسندی محصول هم خوانی داشتند. نتایج حاصل از رگرسیون گام به گام نشان داد که سه صفت قطر ساقه، طول ساقه و تعداد میوه در بوته بیشترین تاثیر را بر روی عملکرد میوه داشتند. جهت ارزیابی اثرات مستقیم و غیرمستقیم صفات وارد شده در مدل رگرسیونی بر عملکرد میوه، تجزیه علیت انجام شد. نتیجه حاصل از این تجزیه موید تاثیر مستقیم سه صفت یاد شده بر روی عملکرد بود و تاثیر غیر مستقیم این صفات چندان قابل توجه نبود. با توجه به این که در این آزمایش لاین های مورد مطالعه از لحاظ تنوع ژنتیکی تفاوت های قابل توجهی در صفات مورد بررسی نشان دادند نتیجه گیری شد که با انتخاب ژنوتیپ های برتر در هر خوشه که فاصله ژنتیکی بیشتری با یکدیگر دارند می توان در تولید ارقام هیبرید فلفل به منظور بهره جستن از هتروزیس استفاده کرد.کلید واژگان: تجزیه به مولفه های اصلی، تجزیه خوشه ای، تجزیه به عامل ها و رگرسیون مرحله ایIn order to investigate the genetic diversity of 65 lines of pepper, collected from different regions of the country and also from China and the International Research Center for Vegetables (AVRDC), a randomized complete block design with 3 replications was done. Results of analysis of variance showed a significant difference among genotypes at 1% probability level for all traits. Based on the mean comparison of different traits using Tukey's method at 5% probability level, genotypes 3095, 0013 and 26-6 were better in terms of yield and characteristics associated with marketable products. To determine the genetic distance and grouping of genotypes, factor and cluster analysis performed. To understand the internal relations of traits and to determine the group of variables with the highest correlation, factor analysis performed using principal component analysis were through varimax rotation. In these analysis, four independent factors justified 74.7% of the variation. Cluster analysis was done using Ward method, and the lines were gathered into six different groups. So that, this grouping was associated with geographic distribution of lines and some of morphological traits that associated with marketability. Results of stepwise regression showed that three traits of stem diameter, stem length and number of fruits per plant had the greatest effect on fruit yield. To evaluate the direct and indirect effects of these traits on fruit yield, Path analysis performed. Results showed that the three mentioned traits had direct effect and indirect effect of these traits was very low. Given that in this experiment lines under study showed significant differences in terms of genetic variability for traits under evaluation. It was concluded in order to benefit from heterosis, selection of superior genotypes with greater genetic distance from each other can be useful in pepper hybrid variety production.Keywords: Cluster analysis, Factor analysis, principal component analysis, stepwise regression
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مجله تحقیقات گیاهان دارویی و معطر ایران، سال سی و چهارم شماره 1 (پیاپی 87، فروردین و اردیبهشت 1397)، صص 115 -130با وجود اهمیت گیاه دارویی بابونه آلمانی (Matricaria chamomilla L.) که یکی از اصلی ترین گیاهان دارویی پرمصرف در سراسر جهان می باشد، اطلاعات ناچیزی در مورد تنوع ژنتیکی درون و بین جمعیتی آن در ایران وجود دارد. این پژوهش با هدف بررسی تنوع ژنتیکی 15 توده بابونه آلمانی براساس خصوصیات مورفولوژیک در قالب طرح بلوک های کامل تصادفی با سه تکرار انجام و صفات ارتفاع، قطر گل، قطر نهنج، وزن تر گل، وزن خشک گل، زی توده تر، زی توده خشک، شاخص گلدهی، درصد اسانس و درصد کامازولن مورد بررسی و تجزیه واریانس قرار گرفت. جمعیت ها از نظر تمامی صفات اختلاف معنی دار (P≤0.01) داشتند. تنوع فنوتیپی و ژنوتیپی برای صفات زی توده تر، زی توده خشک و درصد کامازولن بیش از 60% بدست آمد. وراثت پذیری صفات درصد کامازولن (94.04)، زی توده تر (93.09)، ارتفاع گیاه (90.59)، قطر گل (86.52)، وزن خشک گل (84.15) و زی توده خشک (83.08) مقادیر قابل توجهی بدست آمد. بالاترین و کمترین زی توده خشک مربوط به جمعیت های همدان و اورآ به ترتیب با 9700 و 753 کیلوگرم در هکتار بود. بالاترین درصد کامازولن و درصد اسانس به ترتیب از جمعیت دهرود (14.10)، جم و ریز (0.61) بدست آمد. قطر گل بالاترین همبستگی (0.62) با درصد اسانس داشت. عملیات تجزیه رگرسیون گام به گام برای درصد اسانس به عنوان متغیر وابسته انجام شد که به ترتیب چهار صفت قطر گل، ارتفاع، وزن تر و خشک گل وارد مدل شدند که 59% تغییرات را توجیه کردند. در تجزیه علیت برای درصد اسانس به عنوان متغیر وابسته، بیشترین اثر مستقیم مربوط به وزن تر گل (1.09) و بیشترین اثر غیرمستقیم مربوط به وزن تر گل از طریق وزن خشک گل (1.06) بود. نتایج تجزیه خوشه ای، جمعیت های مورد بررسی را در سه گروه قرار داد که گروه بندی آنها از توزیع جغرافیایی پیروی نمی کرد.کلید واژگان: جمعیت های بابونه آلمانی (Matricaria chamomilla L، )، زی توده، درصد اسانس، رگرسیون گام به گام، تجزیه علیتDespite the importance of the German chamomile (Matricaria chamomilla L.), as one of the most widely used medicinal plants in the world, there is little information about the genetic variation within and between its populations in Iran. This study was conducted to investigate the genetic diversity of 15 chamomile populations based on morphological characteristics in a randomized complete block design with three replications. Height, flower diameter, receptacle diameter, fresh flower weight, dry flower weight, wet biomass, dry biomass, flowering index, essential oil percentage and Chamazulene percentage were analyzed. The populations had a significant difference for all traits (P≤0.01). The phenotypic and genotypic variation was obtained to be more than 60% for dry weight, dry mass and Chamazulene content. Significant values were recorded for the heritability of the traits including percentage of kemazolen (94.04), the wet biomass (93.93), plant height (90.59), flower diameter (86.52), dry flower weight (84.15), and dry biomass (83.08). The highest and lowest yield (kg/ha) were related to Hamedan (9700) and Eurea (753.33) populations, respectively. The highest percentage of Chamazulene and essential oil content were obtained from Dehroud (14.10) and Jam-o-Riz (0.61), respectively. The flower diameter had the highest correlation (0.62) with the percentage of essential oil. Regression analysis for essential oil percentage as the dependent variable was performed and four traits including flower diameter, height, and fresh weight of flower were introduced into the model, explaining 59% of the variation. In the path analysis for essential oil percentage as the dependent variable, the highest direct effect was related to the fresh weight of flower (1.09) and the highest indirect effect was related to the fresh weight of flower (1.06). The cluster analysis grouped the populations into three groups that did not follow geographical distribution.Keywords: German chamomile populations (Matricaria chamomilla L.), biomass, essential oil percentage, stepwise regression, path analysis
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سودمندی هر برنامه اصلاحی با توجه به میزان ارتباط بین عملکرد دانه با عوامل موثر بر آن تعیین می شود. به همین منظور 25 رقم گندم زمستانه، در قالب طرح بلوک های کامل تصادفی با سه تکرار در سال زراعی 91-90 در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه آزاد کرج در دو شرایط آبیاری (آبیاری نرمال و قطع آبیاری بعد از مرحله سنبله دهی) کشت و مورد ارزیابی قرار گرفت. 17 صفت زراعی اندازه گیری و بررسی شد. ضرایب همبستگی ساده صفات، نشان دهنده رابطه مثبت و معنی دار عملکرد دانه با صفات روز تا سنبله-دهی، عملکرد بیولوژیک و شاخص برداشت در شرایط عدم تنش و صفات مرتبط با رسیدگی، عملکرد بیولوژیک، شاخص برداشت و طول بیرون آمدگی پدانکل در شرایط تنش خشکی بود. نتایج حاصل از رگرسیون گام به گام نیز ارتباط بین عملکرد دانه و عملکرد بیولوژیک را تایید کرد. برای صفات وارد شده در مدل رگرسیونی گام به گام تجزیه علیت انجام شد و در هر دو شرایط نرمال و تنش بیشترین اثر مستقیم بر روی عملکرد دانه، متعلق به عملکرد بیولوژیک، بود.کلید واژگان: گندم نان، همبستگی، رگرسیون گام به گام، تجزیه علیتThe usefulness of any corrective program is determined by the relationship between the grain yield and the factors affecting it. For this purpose, 25 winter wheat cultivars were planted and evaluated in a randomized complete block design with three replications in a field experiment at the Faculty of Agriculture, Karaj Azad University, Karaj, Iran under two irrigation conditions (normal irrigation and irrigation after the spike stage). 17 traits were measured and evaluated. Simple correlation coefficients of traits indicated a positive and significant correlation between grain yield and days to flowering, biological yield and harvest index in normal conditions, and traits related to rooting, biological yield, harvest index and peduncle outflow length in drought stress conditions. The results of stepwise regression confirmed the relation between grain yield and biological yield., path analysis was performed for the traits introduced in the stepwise regression model and in both normal and stress conditions the most direct effect on grain yield had belonged to biological yield.Keywords: Bread Wheat, Correlation, Stepwise Regression, Path Analysis
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به منظور بررسی روابط بین عملکرد و اجزای آن در گندم نان، آزمایشی در سال زراعی 91-1390 در مزرعه ایستگاه تحقیقات کشاورزی گنبد در قالب طرح بلوک های کامل تصادفی در سه تکرار بر روی 10 ژنوتیپ گندم نان (مروارید، N-87-4، N-87-9، N-86-6، N-86-8، N-80-19، N-86-5، N-85-5، کوهدشت، لاین 17) اجرا شد. در این آزمایش 7 صفت مورفولوژیک اندازه گیری شد. تجزیه واریانس ژنوتیپ ها برای همه صفات در سطح احتمال 1% معنی دار بود. ژنوتیپ های N-85-5 و لاین 17 به ترتیب بالاترین و پایین ترین عملکرد دانه را به خود اختصاص دادند. از میان تمامی صفات مورد آزمایش تعداد سنبله بارور بالاترین میزان همبستگی (**999/0) را با عملکرد دانه داشت. با استفاده از رگرسیون گام به گام صفت تعداد سنبله بارور به عنوان صفت تاثیرگذار وارد مدل شد که 8/99 % از تغییرات داده ها را توجیه کرد. در ادامه برای یافتن روابط علی صفات، تجزیه علیت برای عملکرد دانه انجام شد که تنها اثر مستقیم و مثبت بر عملکرد دانه مربوط به صفات تعداد سنبله بارور بود. نتایج تجزیه خوشه ایبه روش وارد نشان داد که ارقام مورد مطالعه در دو گروه طبقه بندی شدند و گروه دوم از نظر میانگین عملکرد دانه بیش ترین مقدار (66/4397) را به خود اختصاص داد. با توجه به نتایج بدست آمده می توان اظهار داشت ژنوتیپ N-85-5 دارای بالاترین عملکرد دانه بود و صفت تعداد سنبله بارور به عنوان صفت موثر بر افزایش عملکرد دانه شناسایی شد.In order to investigate relationship between yield and its components in bread wheat, tested during 2011-2012 were conducted in Agricultural Research Station of Gonbadin randomized complete block design with three replications whit 10 bread wheat genotype (Morvarid, N-87-4, N-87-9, N-86-6, N-86-8, N-80-19, N-86-5, N-85-5, Kohdasht, Line 17). In this experiment, were measured 7 morphological traits. Analysis of variance genotypes for all traits was significant at 1% probability level. N-85-5 and Line 17 genotypes produced the highest and the lowest grain yield, respectively. Among all tested traits, the number of fertile spike had the highest correlation (0.999 **) with grain yield. Using stepwise regression, the number of fertile spikes entered the model as an effective attribute, justifying 99.8 percent of the data variation. In order to find the causal relationships, the path analysis was performed for grain yield The direct effect on the grain yield was related to the number of fertile spike traits. The results of cluster analysis by ward method showed that the studied cultivars were classified in two groups and the second group in terms of grain yield was the most (397.66). According to the results, can be said that N-85-5 genotype had the highest grain yield and trait number of fertile spike was identified as an effective trait for increasing grain yield.Keywords: Path analysis, Stepwise regression, Traits correlation, Wheat yield
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با بکارگیری نشانگرهای مولکولی، اصلاح گیاهان با سرعت و سهولت بیشتری انجام می گیرد و انتخاب والدین برای تلاقی های بعدی در برنامه های اصلاحی با اطمینان بیشتری انجام می گیرد. در دسترس بودن تعداد بسیار زیادی از نشانگرها و صفات مورفولوژیکی می تواند به مطالعه تجزیه رگرسیونی بین این نشانگرها و صفات مورفولوژیکی کمک نماید. در این تحقیق، ارتباط صفات مرتبط با عملکرد در 20 ژنوتیپ پسته با استفاده از 15 آغازگر RAPD مورد بررسی قرار گرفت. در نهایت 11 آغازگر چندشکلی نشان دادند و مجموعا 56 قطعه (لوکوس) را تکثیر کردند که از این بین 36 قطعه (29/64 درصد) چند شکلی را با میانگین 09/5 الل به ازای هر پرایمر نشان دادند و میزان این چندشکلی از حداقل 25 درصد برای آغازگر AJ05 تا حداکثر 5/87 درصد برای آغازگر OPAD02 متغیر بود. میانگین محتوای اطلاعاتی حاصل از چند شکلی برای جایگاه ها 23/0 و از 095/0 (AJ05 و OPAD14) تا 39/0 (OPC05) متغیر بود. برای شناسایی نشانگرهای مثبت مرتبط با صفات اجزای عملکرد، تجزیه رگرسیون گام به گام بین داده های مولکولی به عنوان متغیرهای مستقل و صفات مورد مطالعه به عنوان متغیرهای وابسته انجام گرفت. نوزده قطعه RAPD با شش صفت مرتبط با عملکرد ارتباط داشتند. بعضی از نشانگرهای RAPD با بیشتر از یک صفت در تجزیه رگرسیون چندگانه ارتباط داشت که می تواند به خاطر اثر پلیوتروپیک مکان های صفات کمی بر روی صفات مختلف یا پیوستگی ژن های مختلف باشد. برای درک این موضوع تهیه نسل های در حال تفرق و نقشه های پیوستگی ضروری می باشد. همچنین این نتایج می تواند در برنامه های اصلاحی انتخاب به کمک نشانگر هنگامی که هیچ اطلاعات ژنتیکی در دسترس نیست، مفید باشد.کلید واژگان: آغازگر چندشکل، رگرسیون گام به گام، متغیر مستقلIntroductionThe pistachio (Pistacia vera), a member of the cashew family, is a small tree originating from Central Asia and the Middle East. The tree produces seeds that are widely consumed as food. Pistacia vera often is confused with other species in the genus Pistacia that are also known as pistachio. These other species can be distinguished by their geographic distributions and their seeds which are much smaller and have a soft shell. Continual advances in crop improvement through plant breeding are driven by the available genetic diversity. Therefore, the recognition and measurement of such diversity is crucial to breeding programs. In the past 20 years, the major effort in plant breeding has changed from quantitative to molecular genetics with emphasis on quantitative trait loci (QTL) identification and marker assisted selection (MAS). The germplasm-regressioncombined association studies not only allow mapping of genes/QTLs with higher level of confidence, but also allow detection of genes/QTLs, which will otherwise escape detection in linkage-based QTL studies based on the planned populations. The development of the marker-based technology offers a fast, reliable, and easy way to perform multiple regression analysis and comprise an alternative approach to breeding in diverse species of plants. The availability of many makers and morphological traits can help to regression analysis between these markers and morphological traits.Materials And MethodsIn this study, 20 genotypes of Pistachio were studied and yield related traits were measured. Young well-expanded leaves were collected for DNA extraction and total genomic DNA was extracted. Genotyping was performed using 15 RAPD primers and PCR amplification products were visualized by gel electrophoresis. The reproducible RAPD fragments were scored on the basis of present (1) or absent (0) bands and a binary matrix constructed using each molecular marker. Association analysis between molecular date (as independent variable) and morphological data (as dependent variable) was performed using multiple regression analysis to identify informative markers associated with the yield related traits. Multiple regression analysis was conducted using stepwise method of linear regression analysis option of SPSS. Student t-test was performed to assess significance difference between mean trait estimates of genotypes where specific markers were present and absent. Markers shown significant regression values were considered to be associated with the trait under consideration.Results And DiscussionFinally 11 primers were polymorphic and a total of 56 pieces (loci) were amplified that among these, 36 segments (64.29%) showed polymorphism with an average of 5.09% per primers and the rate of this polymorphism ranged from at least 25% for AJ05 primer up to 87.5% for OPAD02 primer. Polymorphic information content ranged from 0.095 (AJ05 and OPAD14) to 0.39 (OP 05), with an average of 0.23. Stepwise regression analysis between molecular data and traits was performed to identify informative markers associated with yield component traits. Nineteen RAPD fragments were found associated with six yield related traits. Some of RAPD markers were associated with more than one trait in multiple regression analysis that may be due to pleiotropic effect of the linked quantitative trait locus on different traits. However, to better understand these relationships, preparation of segregating population and linkage mapping is necessary. Also, these results could be useful in marker-assisted breeding programs when no other genetic information is available.ConclusionThis investigation on molecular markers associated with yield traits in Pistachio has provided clues for identification of the genotypes with higher yield value. In breeding programs selection of quality material is often a time-consuming process, and thus marker-assisted selection could be of great useful in identification of promising genotypes with high value of yield traits. Some of RAPD markers can be used for elite selection of Pistachio, particularly when no other genetic information like linkage maps and quantitative trait loci are available for the species. The applications of the RAPD approach enable us to predict positive correlation between data generated by molecular markers and studied traits. Also, the markertrait association identification will play an important role in plant MAS/QTL breeding programs, especially in plants where genetic information such as linkage map and QTL is not available.Keywords: Dependent variable, Polymorphic primers, Stepwise regression
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به منظور تعیین ارتباط بین عملکرد و اجزای آن و شناسایی صفات مورفولوژیکی موثر بر عملکرد گوجه فرنگی، 97 رقم محلی گوجه فرنگی از دو استان آذربایجان غربی ایران (83 رقم محلی) و اغدر ترکیه (14 رقم محلی) به همراه سه رقم تجاری ’پتوارلی سی اچ‘، ’ریوگرند‘ و ’اچ-2274‘ در قالب طرح آلفا لاتیس با دو تکرار، در ایستگاه تحقیقات کشاورزی کهریز ارومیه به مدت دو سال (92-1391) مورد مطالعه قرار گرفت. نتایج تجزیه واریانس مرکب داده ها نشان داد که تفاوت بین ارقام گوجه فرنگی در کلیه صفات مورد مطالعه معنی دار بود. عملکرد با صفات طول و عرض برگ های لپه ای و حقیقی، تعداد روز تا رسیدگی میوه، وزن میوه، قطر و طول میوه، ضخامت پریکارپ و طول دم میوه، همبستگی مثبت و معنی دار و با تعداد گل در گل آذین، درصد تشکیل میوه در گل آذین، تعداد میوه در گیاه، تعداد روز تا رسیدگی 50 درصد میوه، مواد جامد محلول و اسیدیته همبستگی منفی معنی دار داشت. در بررسی رگرسیون گام به گام، صفات طول میوه، مواد جامد محلول میوه و درصد تشکیل میوه به ترتیب وارد مدل گردیدند. این صفات 43 درصد تغییرات عملکرد را توجیه کردند. براساس نتایج تجزیه علیت، صفات طول میوه، عرض برگ، وزن میوه و ضخامت پریکارپ میوه دارای بیشترین اثر مستقیم مثبت بر عملکرد بودند. لذا می توان از این صفات در گزینش ارقام و برنامه های اصلاحی گوجه فرنگی جهت بهبود عملکرد استفاده نمود.کلید واژگان: تجزیه علیت، رقم محلی، رگرسیون گام به گام، گوجه فرنگی، همبستگیTo determine the relationship between yield and components of it and identify the effective traits on yield, 97 tomato landraces from West Azarbaijan in Iran (83 landraces) and Iğdır in Turkey (14 landraces) along with three commercial cultivars were studied using an alpha lattice design with two replications. The experiment was carried out at the Agriculture and Natural Resources Research Center of West Azerbaijan during two years (2012-2013).Combined analysis of variance indicated significant variation among cultivars for all the experimental characters. Correlation analysis revealed significant positive correlation between yield and length and width of cotyledon and true leaves, number of days to fruit maturity, fruit weight, length of fruit, diameter of fruit and pericarp thickness while significant negative correlation was observed between yield and number of flowers per inflorescence, fruit set per cluster, number of fruits per plant, number of days to 50 percent of fruit maturity, total soluble solids (TSS) and acidity. In stepwise regression analysis fruit length, TSS and percentage of fruit set per cluster were entered to the model, respectively. These characters explained 43 percent of yield variation. Path analysis showed that fruit length, leaf width, fruit weight and pericarp thickness have the most positive direct effect on yield. Thus, these traits could be used as selection criteria in tomato breeding programs for yield improvement.Keywords: Correlation, Landrace, Path analysis, Stepwise regression, Tomato
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این آزمایش با هدف تشخیص هم گروه های گل ده سیر (Allium sativum L.) و تعیین ارتباط صفات مورفولوژیکی با صفت گل دهی با استفاده از روش های آماری تجزیه واریانس، مقایسه میانگین ها، ضرایب همبستگی، تجزیه عامل، رگرسیون گام به گام، تجزیه مسیر و تجزیه خوشه انجام شد. در این پژوهش صفات گل دهی، تعداد، طول و عرض برگ، موقعیت طویل ترین برگ، طول و قطر ساقه مجازی، وزن سوخ و سیرچه، تعداد سیرچه در سوخ، درصد ماده خشک سیرچه و عملکرد در 30 هم گروه سیر ایرانی بررسی شد. نتایج تجزیه واریانس آزمایش بیانگر تفاوت معنا دار بین کلون ها در تمامی صفات ارزیابی شده بود. آزمون ضرایب همبستگی، وجود همبستگی منفی معنا دار بین صفت گل دهی با صفات تعداد، طول و عرض برگ، موقعیت طویل ترین برگ، قطر ساقه مجازی، وزن سوخ و سیرچه، تعداد سیرچه در سوخ و عملکرد، و همبستگی مثبت معنا دار با صفات طول ساقه مجازی و درصد ماده خشک سیرچه را نشان داد. آزمون تجزیه به عامل ها نشان داد که در عامل اول، بیشترین ضرایب مثبت مربوط به صفات تعداد و عرض برگ، قطر ساقه مجازی، وزن سوخ و عملکرد و در عامل دوم بیشترین ضرایب مثبت مربوط به صفات طول برگ، طول ساقه مجازی و وزن سیرچه بود. تجزیه رگرسیون گام به گام نشان داد که صفات تعداد برگ در بوته، طول ساقه مجازی و طول برگ بیشترین همبستگی را با گل دهی داشتند. آزمون تجزیه علیت (مسیر) نیز نشان داد که صفات تعداد برگ در بوته و طول برگ بیشترین تاثیر منفی مستقیم و صفت طول ساقه مجازی بیشترین تاثیر مثبت مستقیم را بر گل دهی داشتند. بر اساس تجزیه کلاستر صفات، کل هم گروه های سیر به دو زیر خوشه گل ده و غیرگل ده تفکیک شدند. نتایج این پژوهش نشان داد صفات مورفولوژیکی موثر بر گل دهی به ویژه طول کمتر برگ، طول ساقه مجازی بیشتر و تعداد کمتر برگ در بوته، می توانند به منزله نشانگرهای مورفولوژیکی در برنامه های به نژادی و تولید بذر سیر استفاده شوند.
کلید واژگان: تجزیه عامل، تجزیه علیت، تجزیه کلاستر، رگرسیون گام به گام، ضرایب همبستگیThis research was designed to identify garlic (Allium sativum L.) bolting clones and determining the relationship between their morphological traits and bolting capacity by using statistical methods of analysis of variance, comparison of means, correlation coefficients, factor analysis, stepwise regression, path analysis and cluster analysis. Traits including flowering ability, number, length and width of leaf, position of the longest leaf, length and diameter of pseudostem, weight of bulb and clove, number of cloves in bulb, percent of clove dry matter and yield were investigated in 30 Iranian garlic clones. Results of analysis of variance showed significant difference in all studied traits of clones. Coefficients of correlation test showed that there was significant negative correlation between bolting and number, length and width of leaf, position of the longest leaf, diameter of pseudostem, weight of bulb and clove, number of clove in bulb and yield; and significant positive correlation with length of pseudostem and clove dry matter percentage. Factor analysis test showed that in first factor, the most positive coefficient was related to number and width of leaf, diameter of pseudostem, weight of bulb and yield, and in second factor, the most positive coefficient was related to length of leaf, length of pseudostem and weight of clove. Stepwise regression Analysis showed that leaf number per plant, length of pseudostem and length of leaf had the highest correlation with bolting. In addition, path analysis showed that, the number of leaves per plant and length of leaf had the highest direct negative effect on bolting whereas pseudostem length had the highest direct positive effect on bolting. Acording to cluster analysis of traits, all clones were divided into two main clusters including bolting and non-bolting. Results of this study showed that some morphological traits such as less leaf length, more length of pseudostem and fewer leaf numbers per plant, could be used as a morphological markers in breeding programs and garlic seed production.Keywords: correlation coefficients, factor analysis, stepwise regression, path analysis, cluster analysis -
Cumin (Cuminum cyminum L.) is one of the most important cultivable medicinal plants in Iran and today, it is the second most popular spice in the world after black pepper. It is essential to know the relationships between yield and its components in cumin breeding programs. Therefore, different multivariate statistical analysis was performed on plant characters in cumin to determine the relationships between seed yield and seed yield components under field conditions. Positive and significant relationships were found statistically between the umbel number/plant, seed number/plant and biomass in all sowing dates. There were also very high correlation coefficients for plant height and number of branches with seed yield/plant at most of the sowing dates. Stepwise linear multiple regression analysis for each sowing dates indicated that 89% to 97.2% of the total variation in seed yield/plant was explained by the variation of the seed number/plant, umbel number/plant and 1000-seed weight in the different sowing dates. Path analysis revealed that seed number/plant had strong direct effects on seed yield of cumin in all sowing dates and 1000-seed weight in most sowing dates had positive direct effects on seed yield/plant which shows their potentials in breeding programs. There were high and significant correlation coefficients between umbel number/plant and plant height with seed yield/plant that was resulted from greatest indirect effects of mentioned traits through seed number/plant. In accordance with results of this research, it can be concluded that seed number/plant and 1000-seed weight are good selection criteria for improving seed yield in the cumin, meanwhile umbel number/plant and plant height have good potential to improve seed yield through indirect selection in breeding strategies.
Keywords: Correlation Coefficient, cumin, Path Analysis, Seed yield, components, Sowing date, Stepwise regression -
In order to determine the correlation between some traits and yield components in three chickpea cultivars as well as cause and effect relationships between them, The experimental plots once crushed (Split plot) the base of a randomized complete block design with four replications in the Shirvan Chardavel region of Ilam,1387-1388 was conducted during the crop year. The main factor of four irrigation treatments, irrigation control, irrigated once in 50% of budding, Irrigation at 50% flowering, and Irrigation filling pods, and sub-factor 3 genotype. Analysis of variance based on the effect of irrigation treatments on grain yield, biological yield, harvest index, The number of fertile pods per plant, seed number per plant and seed weight was significant at the one percent level. Generally performed in a water pod filling stage and the flowering of the 41/3 and 29/3 percent Yield was higher than control. Observations showed that the highest yield significant positive correlation with other traits of biological function and harvest index belonged Grain yield and protein yield had a negative correlation. To remove the effects of ineffective or low impact on yield traits in the regression model, stepwise regression was used. Important traits in grain yield in this study, harvest index, seed weight and seed number per plant, respectively The model has a coefficient of determination(0.999), respectively. Path analysis results showed, harvest index and the highest positive direct effect on grain yield had and the seed weight and number of seeds per plant and a negative indirect effect on performance can be applied.Keywords: Irrigation supplemental, path analysis, stepwise regression, yield, chick pea, trait correlation
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This research was conducted to investigation of traits correlation and the cause and effect relationship among some traits and yield component in sugar beet in salt conditions, the research was conducted in the experimental field of Agriculture Faculty of Ahvaz University. The experimental design was split plot based on RCBD with three replications in determine the most important Affecting sugar yield of sugar beet (beta vulgaris) in saline soil. Main plot were two planting treatment (direct and paper pot transplanting), and sub plot were 3 cultivar (BR1 technical monogerm, monodora and BR1 moltigerm). Results showed that the simple effect of cultivation methods had significant difference and paper pot cultivation was better than direct cultivation. paper pot cultivation had sugar percentage more than direct cultivation. The highest sugar yield obtained in cultivation. According to the results the highest positive correlation between root weight and other traits depended on total fresh and dry weight and root dry weight respectively. Root yield had negative correlation with net and gross sugar percentage, and positive correlation with other traits. To remove the effects of ineffective or low impact from the performance characteristics of sugar beet roots in the regression model was used stepwise regression. In this article the important traits of sugar beet yield included root dry weight, total fresh weight, leaf fresh weight, and collar fresh weight. R2 of model was 0.9994, which means those traits can justify approximately 100 percent variation of root yield. Result of path analysis had showed fresh weight has the most direct and positive effect on produced root and by root dry weight and indirect and negative collar fresh weight traits and by total fresh weight indirect effect on yield. There was a positive correlation among accessible sugar with total dry weight and root fresh weight. Accessible sugar put three traits in to regression model based on stepwise regression model and this variation justify sugar. Root fresh weight can justify only 0.91 variations. Based on path analysis root fresh weight had direct and positive effect and sugar percent had the lowest direct and negative effect on accessible root yield.Keywords: Path analysis, stepwise regression, sugar beets, paper pot cultivation, quantity, quality
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In order to study effect of drought stress on morphologic traits, yield and yield components of 6 S.C hybrids of corn, an experiment was carried out on based of complete randomized block design with three replication under drought stress condition in Khorasan razavi agricultural Research and natural resources institute mashhad, Iran on 2010. Results of analysis of variance showed that there are significant different between all hybrids for all traits. Results of hybrid means comparison showed that S.C704 hybrid was better than others in total leaf number, ear length, row number per ear and yield traits. Regression coefficient showed that ear weight was the highest positive direct effect and cob weight was the highest negative direct effect on total yield. Factor analysis with varimax rotation was performed and sex common factor have been extracted, which describe most of traits variation. First and second factor nomination as ear morphological traits and yield respectively. Cluster analysis with Ward’s method, arrangement hybrids into three different groups. In general results of this experiment showed that, S.C 701 and 704 hybrids of grain corn was better than all evaluated hybrid about tolerance to drought stress under Mashhad climate condition.Keywords: Grain yield, Stepwise regression, Simple correlation, Factor analysis, Cluster analysis
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Attention to Genetic diversity of wild relative plants important as a natural germplasm that are huge source of genetic diversity, study on wild relative plants is important. So for study of synthetic wheat lines that received from international center for maize and wheat research (CIMMYT), on 2008-2009 season crops an experiment including 69 synthetic wheat lines with seven controls (Bam, Sistan, Bahar, Roshan, Kavir, Pishtaz and Akbari) by Alpha lattice design include 2 replications which have been done in the research filed seed and plant breeding research institute of Karaj. The twenty morphological and physiological traits were measured. The biological yield trait has the highest correlation (r=0.77**) with grain yield. Biological yield, harvest index, plant height, penultimate and grain width are five traits that entered into the stepwise regression’s model and explain %95.2 of data variation. In continue for study on relative among traits, path analysis has been done. It showed that biological yield and harvesting index consecutively have 0.685 ** and 0.569 ** highest and positive direct effects and plant’s height has the highest and negative (-0.174 **) direct effect.Keywords: Diversity, synthetic wheat lines, correlation, stepwise regression, path analysis
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In order to investigation the relations among the affective traits on white bean grain yield, a filed experiment was conducted with 46 promising lines of white bean and two improved check cultivars “Dehghan” and “Daneshkadeh” at the research field of Karaj, Seed and Plant Improvement Institute, Iran, in 2008 growing season. The experiment was performed as a randomized complete block design with three replications. The results of the traits’ correlation with the grain yield showed that all the characteristics under investigation have a positive and significant correlation with the grain yield. Among them a remarkable correlation was seen among the grain yield with the number of seeds per plant, the biological yield and the number of pod per plant. In the Regression Analysis, the first trait entering the model was” the number of seed per plant” which justified 73% of the yield alterations by its own. Then these characteristics entered the model respectively: 100 seeds weight, biological yield, pods weight, LAI (R8) and the pod Length and they justified 95% of yield alterations totally. To identify the direct and indirect effects of the traits on the grain yield, path analysis was performed; which showed that the traits of the number of seeds per plant, 100 seeds weight and the biological yield has the most positive and direct effect on the grain yield respectively.Keywords: White bean, correlation, stepwise regression, path analysis, grain yield
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به منظور ارزیابی عملکرد گل در هر بوته و اجزا عملکرد در گل محمدی، آزمایشی در قالب بلوک کامل تصادفی با سه تکرار بر روی 35 ژنوتیپ گل محمدی در ایستگاه تحقیقات مناطق خشک و بیابانی کاشان انجام شد. چهارده صفت مورفولوژیکی و عملکردی اندازه گیری شدند. همبستگی عملکرد گل در هر بوته با صفات وزن تر گل، عملکرد گل در هر شاخه، تعداد گل در هر شاخه و ارتفاع گیاه مثبت و معنی دار و با صفات طول غنچه منفی و معنی دار بود. تجزیه و تحلیل رگرسیون مرحله ای برای عملکرد گر در هر بوته نشان داد که صفت وزن تر هر گل و تعداد گل در هر بوته به ترتیب وارد مدل شدند و 99 درصد تغییرات عملکرد گل در بوته را توجیه نمودند. تجزیه عاملها، 5 عامل پنهانی را معرفی نمود که در مجموع 83.2 درصد از واریانس بین صفات را بیان نمودند. در عامل اول، صفات تعداد گل در هر شاخه، عملکرد گل در هر شاخه، قطر تاج پوشش، تعداد گل در هر بوته، طول نهنج و طول دوره گلدهی دارای بار عامل بالایی بودند. این فاکتور تحت عنوان فاکتور عملکردی نامگذاری گردید. تجزیه و تحلیل ضرایب مسیر نشان داد که تعداد گل در بوته، وزن تر گل و عملکرد گل در هر شاخه بالاترین اثر مستقیم را بر عملکرد گل داشتند. بنابراین، این تحقیق پیشنهاد می کند که تعداد گل در هر بوته، وزن تر هر گل و تعداد گل در هر شاخه می توانند معیار انتخاب مناسبی برای بهبود عملکرد گل در هر بوته در ژنوتیپ های گل محمدی باشند.
کلید واژگان: گل محمدی، همبستگی، تجزیه رگرسیون مرحله ای، تجزیه ضرایب مسیر، تجزیه عاملهاIn order to evaluate the relationship of flower yield per plant and yield components in Rosa damascene Mill., an experiment was conducted in a Complete Randomized Block Design with three replications and with 35 genotypes of Rosa damascena, in Kashan dry land and desert research station. Fourteen characters of morphological and yielding were measured. Flower yield per plant exhibited a significant positive correlation with fresh weight of flower, flower yield per branch, number of flower per branch and plant height, but with bud length had a significant negative correlation. Result of stepwise regression analysis for flower yield per plant showed that fresh weight per flower and number of flower per plant entered the model, respectively, and justified 90 percent of total variation of flower yield per plant. Factor analysis revealed 5 factors which justified 83.2 percent of the total variation among characters. In the first factor, traits of number of flowers per branch, flower yield per branch, canopy diameter, number of flower per plant, length of receptacle and flowering time had greater loadings and was named flower yielding factor. Path analysis showed that number of flower per plant, fresh weight of flower and flower yield per stem had the highest direct effects on flower yield per plant, therefore, this research suggest the number of flowers per plant, fresh weight per flower and number of flowers per branch can be good selection criteria for improving flower yield per plant in Rosa damascene.Keywords: Rosa damascene Mill, Correlation, stepwise regression, path analysis, Factor analysis
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